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Comment Re:With the best will in the world... (Score 1) 486

Nobody minds plugging in, but when you have to plug in for 2-4x the time you can drive at highway speeds, that's ridiculous.. The tesla model S is the best in class with a range of 265 mi/charge. That's 10-12h at 220V, so a 'drive:charge' time ratio of 1:3. Gas engined cars are ~400 mi tank, what, maybe 5 mins to fill? That's a ratio of 80:1, or what, about 2 orders of magnitude better? That's more than you can hand-wave away.

Tesla has a nationwide 135 kWh quick charge network built out and expanding every day that's closer to 6:1, or ~20 minutes every few hours. I've driven several thousand miles on it over the last couple of years.

Comment Re:Larger landing area (Score 5, Informative) 342

The F9 is intended to land with what they call a "Hover Slam" maneuver - the engines decelerate it to zero right above the surface in as little time as possible. The Merlin engines have a limited throttle range, and with the stage empty, just one engine firing at the lowest throttle setting has a thrust-to-weight ratio somewhere around 1.8, so it can't hover. It would decelerate to zero and then start to lift off again if the engine isn't shut off, you'd need a TWR of 1.0 to just counter gravity and make it hover.

Comment Re:if it doesnt work (Score 2) 464

And unlike bifocals/progressive-lens glasses, you can't really orient contacts so that a region with different correction is at the bottom.

I don't use them specifically and couldn't tell the OP if they would help their specific situation, but there are bifocal contacts on the market now. I do use toric astigmatism lenses in one eye which are similar, they're designed in a way that causes them to settle into a certain "up" and "down" orientation when installed.

Comment Re:First 'conjoined' satellites? (Score 3, Informative) 67


Or the Orbcomm OG2 constellation that went up in July...

Launching multiple payloads on a single launch isn't exactly new. It sounds like the innovation here is using the satellites themselves as load structures for each other during launch rather than something like an ESPA ring to save weight and payload volume, but launching more than one satellite per mission is pretty common.

Comment Re:That's a shame (Score 2) 445

The reason people say Yuri Gagarin when you ask who the first human in space was is because Yuri beat Shepard by almost a month (April 12th 1961 vs May 5th 1961).

I've never, ever, heard anyone suggest Shepard didn't deserve Astronaut wings or the title "first American in space" because it was suborbital.

Comment Re:Why so much fuss? (Score 4, Informative) 156

That's a reason why you should protect dealer networks if a company decides to start with that business model.

That's not a reason to protect those dealer networks from an upstart company that never had that business model. Just because GM and Ford made a deal with the devil 50 years ago shouldn't bind a new company to that same business model. Tesla has never had a dealer franchise agreement with anyone, them selling directly does not break any contractual agreement they've entered in to. They have no obligation to respect an agreement Ford or GM made with their dealer network to not compete.

Also as a counter point, Apple sells plenty of things through the half dozen Best Buys in my town. There's also two Apple stores within a 20 minutes drive. Just because a company sells through channel partners doesn't immediately preclude them from selling direct, it depends on the agreement they made with the channel in the first place. Even car dealer arrangements started out with the dealers protected by the franchise agreements themselves, elevating them from simple contract law to specific legislative protections came later.

Comment Re:Spot on (Score 4, Insightful) 156

In many cases they're specifically prohibited from opening one. Cars must be sold through dealers, and dealers must have an arms-length relationship with the manufacturer and can not simply be the manufacturer or a subsidiary of the manufacturer.

Those laws were basically written because while franchise agreements between dealers and manufacturers protected the dealers from direct manufacturer competition, the dealers believed they weren't strong enough and eventually manufacturers and their brands would become strong enough that manufacturers would find a way around them, or simply wait for the agreement to lapse and refuse to renew with that term, that dealers got them codified into law.

Which puts us back to the original point. The law was intended to protect existing franchises from existing dealers. They never anticipated a new manufacturer showing up who didn't want to sell through dealers. The law should not bind Tesla or any other new manufacturer to a business model GM and Ford designed many decades ago that puts the new entrant at a competitive disadvantage.

Comment Re:"An anonymous reader" (Score 2) 112

There was only 1 loss on ascent and 1 loss on decent with too few flights to show if those single losses had a probability of greater than 1 in 500.

Columbia was doomed by the time it finished ascent, it just took until descent for the scope of the damage to become apparent. Arguably both losses in the shuttle program can be considered "on ascent".

Comment Re:I wish them well (Score 2) 146

I think it's more the fact that the whole program feels like it is being stitched together based on which existing technologies and contractors contribute to which congressional seats, rather than which technologies are really a good fit in the long term. As well as the fact that beyond a fairly nebulous manned astroid-capture mission, there doesn't seem to be any great plan or will to have a concrete goal for the booster in general. If Congress earmarked $50B over the next decade to put a research station on the Moon or Mars and insulated it from the year-to-year whims that always infect NASA's budget process it'd be one thing, but they aren't. They're trying to build a rocket and then hope two administrations from now it gets a mission funded.

On the technical side, any believe there's no place for solid motors on crewed flight anymore except to ensure campaign donations from Thiokol and United Space Boosters.

Second, while waiting for the new SSME derivative to get finalized and into production, they intend to fly the existing engine inventory. As one of the larger flown relics from the shuttle program, and with several dozen laying around, many of us would rather see them distributed to smaller museums that didn't get orbiters instead of splashed in the ocean. And as a result of the decision to use up the existing stock, the entire expendable stack is built around an engine that's was originally designed for reusability, with all the cost and engineering penalties that implies, and is ultimately too small for the job anyway. If you don't try to fly the existing SSME stock, something like a larger, more modern F1 derivative may start to make more sense, enabling a more powerful liquid first stage without having to bolt solids on the sides to get it off the pad.

Comment Re:what happens if the chick get pregnant? (Score 2) 240

Fun fact: having a child on Earth also means inflicting an uncertain existence upon them including certain death. That fact doesn't appear to have stopped significant numbers of earthers from breeding either, even in conditions most of us wouldn't want to spend a day in let alone a lifetime.

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